Field of the Invention
The invention relates to a piezoelectric actuator for a servo drive, a servo drive with a piezoelectric actuator and methods for producing a piezoelectric actuator.
Piezoelectric actuators are used, for example, in a servo drive for a fuel injection valve in order to control an injection needle and therefore for controlling an injection process for an internal combustion engine.
German Patent DE 38 44 134 C2 has already disclosed a servo drive having a piezoelectric actuator with a piezoelectric actuator stack which is contained in a drive housing and is surrounded by a hollow cylindrical spring element. The actuator stack and the spring element are clamped between an actuator cap and a displaceable actuator base.